Hey, Ben. Most brands' promo literature will identify the model or models that are good for beginner-intermediate riders. Generally, when the kite is laid out flat on the ground, you'll want a "bowed" shape on the leading edge as opposed to a more rectangular kite shape (sometimes called a "C" kite shape because of the way it looks in the sky). A kite that's described as a low aspect, easy relaunch, bow kite tends to be good for learning and early progression. If you find a kite that looks good, ask on this forum and someone will usually respond.

You may find that you'll be content with a 12-14 meter kite for a year or so. I'd be cautious about immediately buying a 17 meter when summer hits in Florida. A 17 meter kite is useful if you have really good kite skills and can relaunch in very light wind. But if you're still learning, it can be frustrating to try to relaunch and ride a 17 meter kite in really light wind. You may find that it's better to surf or go to the cable park on light wind days, and hold off on kiting until the wind is adequate for your 12-14 meter. But you'll know what you need/want as you gain more experience.

I understand, I will be posting on this forum before I buy anything so I can get feedback from some members. But to be honest, I have done a lot of research and I am almost ready to buy a new SwitchKite Element 6 from http://switchkites.com/element6.html
Did anyone here ever tried one?

I am actually taking my last class on Saturday in the Keys if the weather is fine, and if everything is fine after that I will make my purchase on Sunday. I am really excited!

Thank you for the advice I won't make the mistake to buy a 17m2 Kite right now, I hope I get to practice until the summer with a 14m2 Kite so I can see what I want to do by the summer.

A twintip in the 135-140cm range would be your go-to board. Generally the longer/wider the board is, the better it is toward the bottom end of your kite's range, whereas a smaller board will be better at the upper end of the kite's range. For 170 lbs I'd probably try to find "freeride" twintip around 136cm by 40cm and is fairly flat and medium flex. South Florida is super choppy so you'll either want a lot of rocker or some decent flex so your knees don't explode, but unfortunately florida is also not that windy, so high-rocker boards are kind of out of the question because they're really slow. Every brand has a general do-it-all board that goes upwind well and will serve you in your progression for quite a while.

Some people will say to get a huge board so you can learn to go upwind easier. You can do this if you want to spend the extra money on a second board. A big lightwind board will be useful if you want to try to ride here over the summer when the wind is light... a big board makes a big difference. But, they aren't much fun to ride unless you enjoy riding back and forth in straight lines, so it's up to you. A lightwind specific board would be something like the Liquid Force Overdrive, Best Breeze, and so on. Most people don't go this route, they just jump straight onto a "regular" twintip, but it may be worth it depending on your athletic ability and how quickly you feel you're learning in general.

As far as where to buy a board from, you can get away with a lot more with a board than kites, so feel free to buy something used even if it is cheap. Modern boards are generally tuned up a little better in terms of shape and channeling to help you get grip and go upwind, but it's not really a mind blowing difference. Something like this would be a good place to start looking if you have no idea: http://www.windance.com/137cm-Slingshot-Crisis/39954/ decent price and that's the board shape I am suggesting (low rocker, medium-ish flex).

Thank you for the advices Dylan. When I am about to buy a board, I will post here before to get some feedback
I am most likely gonna get a regular Twintip because I don't want to spend the extra money for a second board. As I learn, if I see that I really need a bigger board for light wind, I will get one.

I just received my gear: I got the Element6 Kite and the Controller 4X. I do have a few questions about it now if someone can help.
I inflated the kite and it seems really big. I think I will use it in 10kts-15kts wind range. For my weight of about 170lbs does that seem fine?

Also, I took about 10 hours of classes and now I am thinking to go by myself to try my kite on the beach and get a feel for it. I know how to use a kite from inflating it to do water starts and riding downwind. But this time I am gonna be by myself without any instructor. My main concern is to pick the right day (right weather and wind) to go test it. Any suggestions?

6 months into kiteboarding now. Probably had over 25 sessions and finally starter to do small jumps. I might get a new board soon. What would you recommend for transition?
Note: the wind literally disappeared here in Florida this summer

6 months into kiteboarding now. Probably had over 25 sessions and finally starter to do small jumps. I might get a new board soon. What would you recommend for transition?
Note: the wind literally disappeared here in Florida this summer

Glad you're progressing! For a new board, depends very much on what you don't like about your current board. It may be that you just need to optimise your current setup.

An easy upgrade would be to get better/adjustable footpads & straps, and you can transfer those to another board.
For example, with a wider board you may want to move the footpads closer to the heel side, if your pads allow that.

Or you can try smaller/bigger fins. Once again, these can be used on other boards.